Explain briefly the difference between using the zscore and

Explain briefly the difference between using the z-score and the boxplot (or IQR) approaches for determining outliers

Solution

The z score method uses the mean and standard deviation to determine which data points are outliers. As mean and standard deviation are more affected by extreme values (as it measures the general variation), they are more subject to change with the outliers.

Meanwhile, the boxplot method uses the quartiles, which is dependent only on the order of the data points, not on the general variation. Hence, it is less sensitive to extreme values.